8mm Forum: Stray Magnetic Fields and Sound

This is topic Stray Magnetic Fields and Sound in forum 8mm Forum at 8mm Forum.

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Posted by Steve Klare (Member # 12) on August 31, 2018, 06:17 AM:

We were watching some films last night. First we watched a silent, then I turned on the audio to run a sound print. Once a second there was a beep coming out the speakers!

This is really bad timing: we had a lightning strike last week and we lost some electronics. It's OK: insurance covered everything and I was relieved I didn't need to explain to Allstate what a movie projector is...or so I thought!

I 'fixed' the problem: turns out to be one for the books. You see the problem was...my Wife!

She had some spinal surgery in June and she wears an electromagnetic pad every night to promote bone regrowth. She was sitting with me while I was running the machine, and I looked over and noticed she was wearing it. I asked her to walk around the room and as she walked away the beeps faded and then died out!

Taken at face value, this may be the most useless technical tip ever written on this forum. (I mean: what are the odds this will happen to anyone else?)

-then again, it's probably worth checking out the immediate area around the machine if you hear something funky in your sound tracks. For example there is a ceiling lamp over my machines with a dimmer. Fully on is fine, so is fully off. Partially dimmed puts a buzz in my sound: the dimmer chopping up the AC to reduce the voltage is putting a signal out my heads are interested in.

So our thought for the day: Maintain a healthy back for quiet sound tracks! (-at least I THINK that's what it is!)

Posted by Paul Adsett (Member # 25) on August 31, 2018, 10:34 AM:

My bet is that you were running an Elmo projector Steve. For whatever reason Elmo's are very susceptible to EMI, light switches, light dimmers, radio stations, Florida thunderstorms, you name it. No such problems with any Eumig's that I have run. Best solution for you, for family viewing with your wife, is to wrap her in aluminum foil.

Posted by Steve Klare (Member # 12) on August 31, 2018, 10:59 AM:

I’d have to ground her too, Paul!

(Talk about being “down to earth“!)

Your Elmo guess is spot on!

Posted by Paul Adsett (Member # 25) on August 31, 2018, 11:29 AM:

Oh yes, I forgot about the ground wire. Well just make sure you poke it into the middle hole of the wall socket!

Posted by Steve Klare (Member # 12) on August 31, 2018, 12:15 PM:

I‘m sure she‘d prefer to remain no worse than “Neutral”
on this issue!

(Then again it might just be a phase...)

Posted by Douglas Meltzer (Member # 28) on August 31, 2018, 02:30 PM:

If only there was some resistance (at the very least) to the plethora of puns presently posted.

Doug

Posted by Steve Klare (Member # 12) on August 31, 2018, 03:04 PM:

Nobody has to read them: re-fuse if you must!

(Personally, I’d rather fight than switch!)

Posted by Paul Adsett (Member # 25) on August 31, 2018, 06:12 PM:

OhmY God!I'm sorry but I just don't have the capacitance for this kind of conductance. Forum members please conduct yourselves with appropriate reluctance.

Posted by Steve Klare (Member # 12) on August 31, 2018, 07:20 PM:

-Just give me an ‘0hm where the buffalo roam!

(But Vultures Graze Willingly!)

Posted by Bill Brandenstein (Member # 892) on September 01, 2018, 05:03 PM:

What shocking punishment of puns!

Posted by Paul Adsett (Member # 25) on September 01, 2018, 07:51 PM:

Bill just couldn't resist jumping in here! [Smile]

Posted by Steve Klare (Member # 12) on September 01, 2018, 09:14 PM:

At times like these we should remember what Popeye said: “I Amp what I Amp!“

(It's just reVolting!)

I was a little concerned about the effect the pulses would have on the stripe: the good news is it looks like it was nowhere near that strong.

Posted by Paul Adsett (Member # 25) on September 01, 2018, 10:40 PM:

This thread has transformed into a high impedance to meaningful discussion. Someone needs to rectify the situation.

Posted by Robert Crewdson (Member # 3790) on September 02, 2018, 05:49 AM:

On a different note; has anyone had music coming from an electrical appliance?. I once read of someone who had music coming out of their vacuum cleaner: an Uncle told me he opened the fridge and heard music coming from it. Had anyone else told me this I would probably have dismissed it. I once heard faintly, a French radio station. I was trying to find the source, then found it was a guitar amp I had just switched on.

Posted by Paul Adsett (Member # 25) on September 02, 2018, 10:36 AM:

[/QUOTE] I once read of someone who had music coming out of their vacuum cleaner[QUOTE]

https://www.youtube.com/watch?v=mIwa9sPFT5I

Posted by Steve Klare (Member # 12) on September 02, 2018, 08:46 PM:

Maybe 30 years ago I went to a Telephone Company Museum in St. John, New Brunswick.

This was immense panels of 1/4" plugs and jacks, brown fabric insulated wires and bakelite handsets and lots'o polished brass and copper.

-a museum pretty much tailor-made for me!

The guide told us this story:

A phone repairman was called out to a lady's house: her phone wouldn't ring. He said he was sorry she missed her calls. She said she was getting all her calls and he asked how.

"My dog screams and then I pick up my phone and somebody is on the other end."

He checked it out: she kept the dog on a metal chain that had gotten looped over her phone line where it entered the house. It had rubbed though the insulation and instead of the 90VAC ringer voltage ringing her phone it was (literally) going to the dog!

Goes to show how cross-talk can happen in highly unpredictable ways!

(Why I love to troubleshoot...once I'm finished!)

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